This invention relates to a hearing aid, in particular a behind-the-ear hearing aid, comprising;
a first unit comprising an amplifier,
a second unit including an electro-acoustic transducer, and intended to be worn in the ear,
first connecting means enabling the electroacoustic transducer to be coupled electrically to the amplifier, and
second connecting means enabling the two units to be inter-coupled mechanically. The second connecting means comprise a tubular element having a first end coupled to one unit, which element accommodates the first connecting means.
Such a hearing aid is disclosed in British Patent Specification No. 792,742 and U.S. Pat. No. 4,291,203. British Patent Specification No. 792,742 describes a behind-the-ear hearing aid in which the first unit is intended to be worn behind the ear and which, in addition to the amplifier, comprises a microphone and a battery. The electro-acoustic transducer in the second unit is the loudspeaker (also referred to as an earphone.) The first connecting means provide an electrical coupling between an output of the amplifier in the first unit and the loudspeaker in the second unit. U.S. Pat. No. 4,291,203 describes a hearing aid in which the first unit is intended either to be worn behind the ear or to be incorporated in a spectacles frame. In addition to the amplifier, the first unit comprises a loudspeaker and a battery. The electro-acoustic transducer in the second unit is the microphone. Thus, the first connecting means establish an electrical coupling between the microphone and an input of the amplifier.
It has been common practice to design the first and the second connecting means as to the length and shape thereof so that they match the shape of the ear. As a result, they are less conspicuous, see for example the above-mentioned British Patent Specification No. 792,742.
This tailoring of the first and the second connecting means, which has to be done by the hearing aid retailer or by an audiologist, is an intricate and time consuming job in the case of the hearing aids described in the above-mentioned publications.